Technical Abstract:
Avian influenza (AI) is a viral disease of poultry that remains an economic threat to commercial poultry throughout the world by negatively impacting animal health and trade. Strategies to control avian influenza (AI) virus are developed to prevent, manage or eradicate the virus from the country, region, state, county or farm. Vaccination with high quality efficacious vaccines that are properly delivered can contribute to the control of avian influenza (AI) outbreaks when used as part of a comprehensive control program that includes enhanced biosecurity, increased surveillance, education of poultry workers, and elimination of infected poultry. However, most types of vaccination still cause problems with disease protection because it is hard to differentiate infected from vaccinated animals (DIVA). Several different DIVA strategies have been proposed for avian influenza to overcome this limitation. Vaccination is a potentially powerful tool for supporting eradication programs by increasing the resistance of birds to field challenge and by reducing the amount and duration of virus shed in the environment. Critical to the success of a vaccination program to control AI, is monitoring flocks for field virus exposure so appropriate measures can be taken. Advances in biotechnologies will overcome some existing limitations in vaccine production and vaccination implementation resulting in vaccines that can be grown in tissue culture systems for more rapid vaccine production; with optimized protection as the result of closer genetic relationship to field viruses through reverse genetics and gene insertions in vector systems; can be mass applied by aerosol, drinking water or in ovo administration; and provide easier strategies for identifying infected birds within vaccinated populations; i.e. DIVA.